Apparatus for producing core yarns



Nov. 11, 1958 s. P. PARKER APPARATUS FOR PRODUCING CORE YARNS 702 V k v m B n A E w v ATTORNEYS APPARATUS FOR PRODUCING CORE YARNS Samuel P. Parker, La Grange, Ga., assignor to Callaway Mills Company, La Grange, Ga., a corporation of Georgia Application May 10, 1957, Serial No. 658,412

3 Claims. (Cl. 57-36) The present invention relates to a method and apparatus for producing core yarns.

It has heretofore been known that the strength of yarns and of fabrics produced from those yarns can be increased by utilizing a core of one type of yarn and a cover or wrapping of a different type of yarn. For example, a yarn which has high strength but which has other properties which might be undesirable in a finished fabric may be used as the core and the wrapping may be of yarns of inherently lower strength but which have other qualities making their use desirable.

The present invention is more particularly concerned with the production of core yarns in which the core is a high strength, continuous filament yarn such as nylon, rayon, or a polyester fiber derived from terephthalic acid and ethylene glycol, and in which the covering or wrapper is of staple fibers such as cotton fibers. Fabrics produced from such yarns have high strength for their weight and have the appearance and feel of fabrics produced from staple fiber yarns. I have found, however, that it is of the utmost importance that the staple fiber cover or wrapping completely and totally cover the core. This is necessary because the staple fibers of the cover will be more or less receptive to dyes than the continuous filament yarn of the core and if the core is not completely covered the yarn, after dyeing, will have an undesirable appearance. Fabrics produced from core yarns are suitable for use as tire fabrics, or as other fabrics which must adhere to rubber or plastic. The continuous filament yarn forming the core has poor adherence to rubber or plastic while the staple fibers of the cover have good adherence to rubber. This is another reason why it is essential for the wrapping to completely cover the continuous filament yarn of the core.

One of the primary objects of the invention isv to rapidly and economically produce a core yarn in which a continuous filament yarn core is totally and completely covered by a wrapping of staple fibers.

Another object of the invention is to produce a core yarn in which a continuous filament yarn core is centered within a staple fiber cover so that the staple fiber cover is of substantially uniform thickness around the core.

Still another object of the invention is to provide a method and apparatus for producing core yarn having the qualities set forth in the foregoing objects of the invention, such production utilizing a spinning frame which has undergone a minimum of modification.

Other objects and advantages of the invention will be pointed out in the following detailed description of the invention which has reference to the accompanying drawing, wherein:

Figure l is a more or less diagrammatic cross-sectional view of a spinning frame which has been modified or adapted for the purposes of the invention;

Figure 2 is an enlarged and more or less diagrammatic view partly in front elevation and partly in vertical crosssection, showing the relationship between the bottom front roll of the spinning frame, the continuous filament States Patent 0.

2,859,583 Patented Nov. 1 1, 1958 yarn feed roll and the continuous filament yarn guide means; and

Figure 3 is an enlarged transverse sectional view through a core yarn and taken in the direction of the arrows along the line 33 of Figure 2.

Many of the elements illustrated in the drawing are elements of a conventional long draft spinning frame and require only brief description. The base 4 of the spinning frame supports a creel in which are positioned bobbins 5 of rovings of staple fibers such as cotton fibers. The apparatus is illustrated as spinning with double roving, which is preferred, although spinning from a single roving is possible. The rovings 6 and 7 pass through a roving guide 8 mounted on a bar 9 to which is imparted the usual traverse motion. The rovings then pass be tween the top and bottom back rolls 10 and 11 and between the middle top roll 12 and an apron 13 which runs over the bottom middle roll 14, a nose 15 and a tension roll 16. Above the nose 15 is the usual control roll 17. The strand or ribbon of staple fibers then passes between the front top roll 18 and the front bottom roll 19. From the front drawing rolls 18 and 19 the strand or ribbon passes through a pigtail yarn guide 20, through a traveler 21 on a ring 22 and to a bobbin 23 on a spindle 24. The elements thus far described are conventional in long draft spinning frames. It will be understood that while the drawing illustrates only a cross-section through one side of the spinning frame, there will be a large number of sets of drawing rolls and spindles on each side of the spinning frame.

Above the roving creel is a shelf 25 which supports bobbins 26 of continuous filament yarn, such as those mentioned above, which is to form the core of the core yarn.' A single continuous filament yarn 27 is drawn from one of the bobbins 26 through a guide bar 28 and a feed tube 29 by means of a yarn feed roll 30. The continuous filament yarn 27 is wrapped one or more times about the feed roll 30 so that the yarn 27 is positively advanced upon rotation of the feed roll. The yarn 27 passes from the feed roll 30 into a groove 31 in a guide bar 32. The guide bar 32 reciprocates as indicated by the arrow 33 in synchronism with the traverse motion of the roving guide 8. This synchronized traverse motion of the guide bar 32 and the roving guide 8 assures that the groove 31 in the guide bar 32 will always be in position to feed the continuous filament yarn 27 between the front drawing rolls 18 and 19 in longitudinal alignment with the center line of the ribbon of staple fibers passing between those drawing rolls, as clearly shown in Figure 2. In that figure the ribbon of staple fibers is shown in broken lines and is designated by the reference numeral 34.

It is imperative to the success of the invention that the peripheral or surface speed of the continuous filament yarn feed roll 30 be less than the surface speed of the bottom front drawing roll 19. One convenient way of driving the feed roll 30 to maintain proper relationship of its surface speed with the surface speed of the bottom front drawing roll 19 is shown in the drawing. A gear 35 is fixed to the shaft of the bottom front drawing roll 19. The gear 35 drives an idler gear 36 which in turn drives a gear 37 fixed to the shaft of the yarn feed roll 30. There are more teeth on the gear 37 than on the gear 35, and, if the bottom front drawing roll 19 and the yarn feed roll 30 are of the same diameter as illustrated, the surface speed of the yarn feed roll 30 will be less than that of the drawing roll 19. By way of example, the number of teeth in the gear 35 might be twelve and the number of teeth in the gear 37 could be fourteen. If the feed roll 30 is driven too slowly there will be slippage of the continuous filament yarn 27 between the front rolls 18 and 19 which will cause slubs in the finished product. On the other hand, if the surface speed of the feed roll 30 is equal to the surface speed of'the front rolls 18 and 19 the continuous filament yarn 27 will not be completely covered by the staple fibers. The surface "spe'ed of the feed roll '30 should be such as to apply tension to the continuous filament yarn without, however, causing any noticeable slippage between the yarn and the front rolls 18 and 19. It will be understood, however, that interchangeable gears of different sizesmay be used to vary somewhat the relative surface speeds of the drawing roll 19 and the yarn feed roll 30 to accommodate different weights and sizes of yarns so long as the surface speed of the yarn feed roll 30 always remains less than the surface speed of the drawing roll 19.

The ribbon of staple fibers 34 with the continuous filament yarn 27 disposed along its center line leaves the front drawing rolls 18 and 19 and a twist is imparted thereto as this assembly passes toward pigtail 20 and toward the ring, traveler and spindle assembly described above. The twisting operation causes the ribbon 34 of staple fibers to be wrapped uniformly about the continuous filament yarn core 27 as clearly indicated by the portion designated by the reference numeral 38 in Figure 2. A cross-sectional 'view of the core yarn is illustrated in Figure 3 on an enla ged scale.

The yarn guide bar 32 extends the full length of the spinning frame as does the roving guide bar 9. The traverse motion of these two members can be imparted by the same cam mechanism. The shaft of the yarn feed roll 30 also extends the full length of the machine so that all yarn feed rolls 30 are driven by the same shaft. As is customary in spinning frames, all of the bottom feed rolls 19 are driven in unison. In this manner there will be a constant diiferential between the surface speed of each bottom front drawing roll and each yarn. feed roll in the spinning frame so that core yarns of uniform quality will be produced on each spindle. The fact that the continuous filament yarn core 27 is positively fed by yarn feed roll 30 eliminates any problems which might be created by lack of uniform tension between the bobbins 26 and bottom roll 15 The amount of twist imparted to the core yarn can be varied in the customary manner and the amount of twist does not appear to be critical in order to obtain complete and uniform coverage of the continuous filament core 27. A highly satisfactory product can be obtained by the use of standard warp twist. The invention enables a core to be completely covered by the wrapping even when the core constitutes as much as sixty-five percent or more of the weight of the yarn. The spinning frame can be provided with any suitable clearer such as the revolving top clearer 39.

Having thus described my invention, I claim:

1. Apparatus for producing a core yarn comprising: a ring spinning frame having a roving creel, drawing rolls, a spindle and a ring and traveler; a support for a supply of continuous filament yarn; a yarn feed roll for positively advancing a continuous filament yarn from such supply toward the front drawing rolls; means for driving said yarn feed roll at a surface speed slightly less than the surface speed of said front drawing rolls; and yarn guide means for guiding the continuous filament yarn from said yarn feed roll between said front drawing rolls in longitudinal alignment with the centerline of a ribbon of staple fibers passing between said front drawing rolls.

2. Apparatus for producing core yarns comprising: a ring spinning frame having a roving creel, drawing rolls, spindles and rings and'travelers; a support for a supply of continuous filament yarns, a yarn feed roll for positively advancing a continuous filament yarn from such supply toward each pair of front drawing rolls; means for driving said yarn feed roll at a surface speed slightly less than the surface speed of said front drawing rolls; and yarn guide means for guiding the continuous filament yarns from said yarn feed rolls between said front drawing rolls in longitudinal alignment with the centerline of ribbons of staple fibers passing between said front drawing rolls.

3. Apparatus for producing a core yarn comprising: a ring spinning frame having a roving creel, drawing rolls, a spindle and a ring and traveler; a support for a supply of continuous filament yarn; yarn feed means for positively advancing a continuous filament yarn from such supply toward the front drawing rolls; means for driving said yarn feed means at a rate to advance said continuous filament yarn at a speed slightly less than the surface speed of said front drawing rolls; and yarn guide means for guiding the continuous filament yarn from said yarn feed means between said front drawing rolls in longitudinal alignment with the centerline of the ribbon of staple fibers passing between said front drawing rolls.

References Cited in the file of this patent UNITED STATES PATENTS 2,024,156 Foster Dec. 17, 1935 2,526,523 Weiss Oct. 17, 1950 2,783,608 Hasler Mar. 5, 1957 

